The invention relates generally to a web and an associated web handling and working machine which feeds the web longitudinally of itself and works on the web as it is fed. The invention deals more particularly with a code on the web which the machine reads as the web is fed, the code providing such information as the length of the web remaining for use.
The present invention may be used with any one of various types of machines such as a plotting machine, a recording machine or the signmaking machine described in U.S. Pat. No. 4,467,525 to Logan, issued on Aug. 28, 1984, assigned to the assignee of the present invention and hereby incorporated by reference as part of the present disclosures. The sign making machine works on sign making web stock which is stored as a roll and drawn by a pair of feed sprockets having pins which cooperate with rows of holes in two side edge portions of the web.
Information describing a desired sign pattern such as an alphanumeric inscription or a geometric shape is programmed into the machine to cause it to automatically cut the pattern from a continuous length of the web. It is important that enough web remain on the roll to make such a pattern before the machine begins to cut it because the machine may not be equipped to continue cutting a pattern on a fresh roll if the previous roll is short, in which case the cut portion of the previous roll is wasted. In this machine and others, a machine operator is usually required to estimate, by visually observing the roll, whether enough web remains to make the desired pattern. However, when little web remains on the roll and the desired pattern is long, the estimation may be inaccurate.
Furthermore, the signmaking machine described above and other web working machines may handle a variety of types of webs and may operate with various types of instruments, and it is important that the proper instrument be utilized for the particular web being fed and that the instrument be operated in the proper manner. For example, the sign making machine is often used to plot a sign pattern on a paper web before the relatively expensive sign making stock is cut, in which case it is important that the operator install a plotting tool within the machine and apply the proper weight, if any, needed to develop a requisite stylus pressure.
After an operator is satisfied with the plot of the desired sign, he or she substitutes signmaking stocl for the paper web and selects a suitable cutting instrument. For most types of signmaking stock, a knife blade is required in which case it is important that the operator program the signmaking machine to maintain the blade tangent to the line of cut.
The operator typically relies upon his or her memory, written instructions or trial and error to select the proper instrument and stylus pressure weight and, if a cutting blade is required, to program the machine to maintain the blade tangent to the line of cut. However, errors occur.
Accordingly, a general aim of the invention is to provide a web handling and working system which reduces errors of the foregoing types.
A more specific aim of the invention is to provide a web handling and working system including a coded web and a web handling and working machine capable of reading the code, which code includes such information as the length of the web remaining on the roll, the type of instrument suitable to work on the web, the weight if any required to develop a suitable stylus pressure, and/or if a knife blade is utilized, the fact that the instrument should be maintained tangent to the line of cut.
Another specific aim of the present invention is to provide a coded web for a web handling and working machine of the foregoing type.
Other aims and advantages of the invention will become apparent from the following detailed description of the preferred embodiments and the accompanying drawings.